Chaeles h



G. H. CARTER.

Electric Burglar-Alarm.

No. 225,271. Patented Mar. 9, I880.

N-PETERS. FHOTOLIUWGRYAPHER. WASNINGTON, D. C.

UNITED STATES PATENT OFFICE.

CHARLES E. CARTER, 0F RRooKLYN, NEW YORK.

ELECTRIC BURGLAR-ALARM.

SPECIFICATION formingpart of Letters Patent No. 225,271, dated March 9,1880.. Application filed December 16, 1879.

To all whom it may concern Be it known that I, OHARLEs H. CARTER, ofBrooklyn, in the county of Kings and State of New York, have invented anImproved Electric Alarm for Fires, Burglars, &c., of which the followingis a specification.

I make use of an open circuit to the window, door, thermostat, or otherplace where an alarm is to be operated, and when the circuit is closedthe current from the battery acts in the electro-magnet and moves acircuit-changing device, so that the instrument is converted into anautomatic electric alarm that continues to sound until set, the samebeing made independent of the opening or closing of the port-ion of thecircuit that extends to the window, door, or thermostat.

By this means the alarm will be given and continue, and the closing ofthe door or window will not cause it to stop, and only one battery andone electro-magnet are made use of.

In the drawings, Figure l is a side view of the instrument with the bellin section, and Fig. 2 is a diagram of the circuit connect-ions.

The electro-magnet a is provided with an armature, Z), swinging onpivots c, and carrying the spring-arm and hammer cl for the bell f.

The contact-screw e and spring 0 on the armature are of the characterusual in automatic electric alarms.

The lever g is provided with a rod, h, passing through the bed B of theinstrument. It is raised by the spring 2, so that the end of the lever gis made to bear upon a projection, 4, upon the hammer when the hammer isnot acted upon by the magnet; but when the hammer is moved theprojection 4, passing from beneath the end of the lever g, allows thespring 2 to lift the rod h, and by a pin, 5, that projects from said rodh, bring the insulated circuit-closing spring Z into contact with thespring 0.

Upon reference to the diagram, Fig. 2, the operation of this instrumentwill be understood.

The battery A is connected to the posts 7 and 8. The post 7 isinsulated, but the post 8 is in contact with the metal base. The dottedline 9 represents this circuit-connection through the base to the pivotsc of the armature 12,-] thence the current passes by the bellarm d,lever g, and insulated wire 10 to the post 11, and to the variouswindows, doors, or thermostats, the same being indicated by acircuit-closer at r, and the return-circuit is to the binding-post 12and wire 13, to the electro-magnet a and wire 14, to the post 7 andbattery. If, now, either of the alarm-circuit closers is operated byopening a door or window, or otherwise, the circuit is completed at r,the magnet on attracts the armature b, strikin g the bell. This movesthe projection 4 from beneath the lever g, the spring 2 acts, raisingthe rod h, and by the pin 5 bringing the spring l into contact with 0and closing a local-circuit through 9, armature b, contactpoint 6, wire16, springs 0 and l, to 12 13, electro-magnet a, and Wire 14 to 7 andbattery.

The motion of the armature opens and closes the circuit by making andbreaking contact with the spring 0 and points and ringing the bellautomatically and continuously until the circuit between l and 0 isbroken and between lever g and hammer-projection 4. It is restoredbymoving the rod h downwardly, so that the latch end on the lever gpresses back the hammer-projection and the latter springs back beneaththe lever. By this arrangement of circuits the continuous alarm isinsured and the instrument rendered very simple.

The circuit-closin g springs 0 [may be placed near thebell instead ofbelow the base.

I claim as my iuvention l. The combination, with the electro-magnet andalarm, of the circuit-closing springs 0 l, lever' g, hammer,circuit-wires, armature b, and contact-point e for the armature,substantially as. and for the purposes set forth.

2. The combination, in an electric alarm, of one battery, oneelectro-magnet, alarm mechanism, a main open circuit, a local circuit,and circuit closing devices, substantially as set forth, whereby theclosing of the main circuit causes the electro-niagnet to operate themechanism that disconnects the main circuit from the electro-magnet andestablishes a local circuit from the same battery through the sameelectro-magnet to give the alarm, substantially as specified.

Too

Signed by me this 15th day of December,"

CHARLES H. CARTER.

Witnesses WILLIAM G. MOTT, GEo. T. PINOKNEY.

